The present invention relates to safety ski bindings. Ski bindings lock or latch to grip a ski boot, generally by gripping the edge of the sole at the heel and the toe, and hold it, and the skier whose leg is in the boot, to a ski. A binding is attached, for example, by screws, to a ski. A safety ski binding is designed to release the grip on a ski boot when the skiing forces on the boot and skier's leg exceed some predetermined threshold which threatens the safety of the skier. It is known in the art that the skiing forces may be detected mechanically or electronically. See U.S. Pat. No. 4,291,894, issued Sept. 29, 1981 to D'Antonio and Bates.
For convenience in use, it is desirable that a safety ski binding be of the "step-in" type. In that type of binding, the skier cocks the release mechanism by stepping into the binding. Other binding types require particular cocking actions by the skier in addition to stepping into the binding. Some bindings require the throwing of a lever before the binding is ready for use. The known electronic safety ski bindings, for example the type shown in U.S. Pat. No. 4,130,296 issued Dec. 19, 1978 to D'Antonio and Bates, require a skier to cock the release mechanism manually in order to prepare the binding for use.
It has been found that a latched binding which grips the sole of a boot tightly against the ski results in discomfort and fatigue for the skier during long periods of use. Many bindings are also limited in their latching position to use with a particular thickness of boot sole. A change of boot style or type usually requires a mechanical adjustment or remounting of the binding on the ski to accommodate a change in sole thickness. In the present invention, these difficulties are overcome by providing a yielding heel piece for gripping the sole of a ski boot adjacent the heel of the boot. While in its latching position, the inventive heel piece yields, i.e., moves through a limited range relative to the surface of the ski in response to forces having magnitudes below the predetermined, threatening threshold level. The yielding movement reduces the skier fatigue that is experienced with latched bindings that do not yield with respect to a ski. The yielding movement also permits a large range of sole thicknesses to be accommodated in the latched binding without mechanical adjustment of the binding.